Myrosinase, action

Glucobrassicin is a mustard oil glucoside found in various Bras-sica spp. (50). 3-Indoleacetonitrile (IAN) is released from glucobrassicin by the action of the enzyme myrosinase at pH 4.0. How-... 

R-C(=0)-NH0H RNCO RNHCOOH RNH2 + CO2. A thio-Lossen rearrangement has been proposed to occur spontaneously for the product generated by the action of myrosinase on sinigrin. ... 

Figure 5.39 Action of myrosinase on sinigrin and the tropeolin-based Dolphin-Withers inactivator.

This study focuses on the determination of the characteristic odorants of wasabi in comparison with those of horseradish by calculation of the logarithmic ratio between the concentration of isothiocyanate and its odor threshold value. The relationship between the yields of the isothiocyanates formed by the action of wasabi myrosinase and the conditions of hydrolysis are presented. 

Figure 1. Structure of the thioglycoside progoitrin present in rapeseed and the products produced by the action of the enzyme myrosinase...

There are two rich sources of organosulphur compounds from plants (1) Alliaceae family containing alliin-alliinase system and (2) Cruciferae (Brassicacae) family e.g. Brassica juncea, Wasabia japonica (wasabi), Armoracia rusticam (horseradish) and Brassica oleracea (cauliflower) containing glucosinolate-myrosinase (Mithen 2006). A number of sulphur-containing compounds can be derived from these plants through the action of myrosinase and alliinase enzymes. 

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